The two brightest stars of this constellation, Sualocin (Alpha Delphini) and Rotanev (Beta Delphini), are not names dating from antiquity, but instead date from a star catalogue of 1814 that was published at the Palermo Observatory in Italy. When read backwards, they form the name Nicolaus Venator which is the Latinized version of the name of the assistant director of that observatory at that time, Niccolò Cacciatore (both Cacciatore and Venator mean hunter).

In Greek mythology, the god Poseidon wanted to marry Amphitrite, a beautiful nereid. She, however, wanting to protect her virginity, fled to the Atlas mountains. Her suitor then sent out several searchers, among them a certain Delphinus. Delphinus accidentally stumbled upon her and was able to persuade Amphitrite to accept Poseidon's wooing. Out of gratitude the god placed the image of a dolphin among the stars.